International Journal of Computer Science Trends and Technology (IJCST) – Volume 3 Issue 3, May-June 2015 ISSN: 2347-8578 www.ijcstjournal.org Page 207 An Approach To Incentive-Based Reputation For Mobile Ad Hoc Networks Vivek Richhariya [1] , Praveen Kaushik [2] Department of Computer Science & Engineering, LNCTS [1] Department of Computer Science & Engineering, MANIT [2] Bhopal M.P - India ABSTRACT MANETs find their use particularly in the field where infrastructured network are not possible without having any centralized administration. Where this feature helps in rapidly deploying and establishing the ad hoc networks, it makes it highly susceptible for attacks by the selfish nodes present in and around the network. To discourage such misbehaviour, we propose reputation-based incentive mechanism to motivate the selfish nodes to cooperate in order to packet forwarding. Incentive will be earned by the intermediate nodes which are responsible for forwarding the packet. In this paper, a cluster head will be used as reputation management of each cluster in the network. This paper highlights various views of cooperation enforcement mechanism and reliability. We perform an overall analysis of our paper by simulation using the network simulator (NS- 2) with the help of AODV protocol. Keywords:-Incentive scheme, reputation; cluster head, ad hoc network I. INTRODUCTION A mobile ad hoc network is a collection of wireless nodes that can dynamically be set up anywhere and anytime without using any pre-existing network infrastructure. In other words, it is an autonomous system of mobile hosts in which they are connected by wireless links are free to move randomly and often act as routers at the same time. Every node in an ad hoc network must be willing to forward packets for other nodes. Therefore, every node in MANETs acts both as a host and as a router [1]. When data transfer is required between any pair of non-adjacent nodes, the network relies on the nodes between them to forward data packets. However, because mobile nodes are typically constrained by power and computing resources, so a selfish node may not be interesting to use its resources to always forward packets that are not of its concern, even though it would expect others to forward its packets [2]. In this circumstance, encouraging the nodes’ cooperation in the packet relaying process is of primary importance. Therefore we want to motive the node become cooperative by assigning different incentive and instead of punishing the selfish node. In this paper, the detection of selfish node are performed by using promiscuous overhearing of neighboring node when node drop packet in order to save their energy. Apart from this, the reputation value and incentive value of each node are placed at the cluster head. With these values cluster head isolate the selfish node from the network. The remainder of this paper is organized as follows. Section 2 provides misbehaving nodes in ad hoc networks. Section 3 presents related works in node cooperation in MANETs using reputation approach. The overview of the proposed system is presented in section 4 and section 5 respectively, followed by the simulation result which was implemented on the NS2 simulator in section 6. Then, the conclusion is drawn in section 7. II. MISBEHAVING NODES IN AD HOC NETWORKS An easy way to comply with the In an ad hoc network, the communication range of mobile nodes is limited on account of power constraint. Therefore, when communication is done between two nodes beyond the transmission range, node depends on intermediate nodes to forward the packets. Due to this reason, sometimes these intermediate nodes do not work as expected. In order to preserve their limited resources such as bandwidth, energy etc, such nodes are called non cooperative nodes or misbehaving nodes[3]. They are of following types: A. Selfish Node The limited battery-power, one of MANET characteristics, encourages nodes to use the network for their own communication only, and not for the gain of other nodes. Refer to routing protocols [4], the following selfish behaviors are considered.  A selfish node drops routing messages or it may modify the Route Request and Reply packets by changing TTL value to smallest possible value.  A selfish nodes participates in the routing protocol, but may drop part or all the data packets that do not belong to it. This node is interested in saving its battery power, apart from having the capability to receive and forward its own packets. B. Malicious Node RESEARCH ARTICLE OPEN ACCESS